Primary pancreatic leiomyosarcoma with metastasis to the liver diagnosed by endoscopic ultrasound-guided fine needle aspiration and fine needle biopsy: A Case Report and Review of Literature.

Primary pancreatic leiomyosarcomas are rare tumors of the pancreas that are usually diagnosed after resection or by biopsy. One case in the literature has utilized endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) cytology. We report a second case of a primary pancreatic leiomyosarcoma that yielded diagnostic material on EUS-FNA cytology. A 72-year-old female presented with 3-4 months of abdominal pain. A CT scan showed a large heterogeneous, lobulated pancreatic head and uncinate mass and multiple hypoattenuating liver lesions. An EUS-FNA was performed on one of the liver lesions with a 25-gauge needle, yielding an adequate sample with lesional cells. The initial read was a spindle cell neoplasm. A subsequent endoscopic ultrasound-guided fine needle biopsy with a 22-gauge needle was performed on the pancreatic head mass to rule out two primaries and to provide tissue for a mitotic index in the case of gastrointestinal tumor. Both the cell block of the EUS-FNA and the core biopsy were equally cellular and showed interlacing spindle cells that stained positive for SMA and negative for DOG-1, CD 117, and CD34. In addition, the core biopsy of the pancreas stained positive for Desmin. A diagnosis of a primary pancreatic leiomyosarcoma was made and the patient was started on systemic chemotherapy. Primary pancreatic leiomyosarcomas are rare pancreatic tumors that may yield diagnostic material by EUS-FNA with a 25-gauge needle. Diagn. Cytopathol. 2016;44:1070-1073.